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How to concatenate strings of a string field in a PostgreSQL 'group by' query?
... asked for, even letting you specify the delimiter string:
SELECT company_id, string_agg(employee, ', ')
FROM mytable
GROUP BY company_id;
Postgres 9.0 also added the ability to specify an ORDER BY clause in any aggregate expression; otherwise, the order is undefined. So you can now write:
SELEC...
How to detect if a stored procedure already exists
... After that, you can ALTER the stored procedure to your liking.
IF object_id('YourSp') IS NULL
EXEC ('create procedure dbo.YourSp as select 1')
GO
ALTER PROCEDURE dbo.YourSp
AS
...
This way, security settings, comments and other meta deta will survive the deployment.
...
Sqlite primary key on multiple columns
...ent, it is an error." Yes, the railroad diagrams might indicate that is valid as well, but the text below clarifies that it is not.
– Brian Campbell
Mar 23 '11 at 19:03
11
...
Remove array element based on object property
... if the array is a tree structure ar beforeDeleteOperationArray=[ { "id": 3.1, "name": "test 3.1", "activityDetails": [ { "id": 22, "name": "test 3.1" }, { "id": 23, "name": "changed test 23" } ] } ] and I want to delete id...
Cast an instance of a class to a @protocol in Objective-C
...c is a UIViewController object that conforms to MyProtocol", whereas using id <MyProtocol> translates to "vc is an object of an unknown class that conforms to MyProtocol".
This way the compiler will give you proper type checking on vc - the compiler will only give you a warning if any method ...
What is the syntax for an inner join in LINQ to SQL?
... DealerContact
join dealer in Dealer on contact.DealerId equals dealer.ID
select contact;
Since you are looking for the contacts, not the dealers.
share
|
...
List the queries running on SQL Server
...
This will show you the longest running SPIDs on a SQL 2000 or SQL 2005 server:
select
P.spid
, right(convert(varchar,
dateadd(ms, datediff(ms, P.last_batch, getdate()), '1900-01-01'),
121), 12) as 'batch_duration'
, P.program_name
...
Insert, on duplicate update in PostgreSQL?
...ause. with the following syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group archives ...
Best way to store a key=>value array in JavaScript?
...
That's just what a JavaScript object is:
var myArray = {id1: 100, id2: 200, "tag with spaces": 300};
myArray.id3 = 400;
myArray["id4"] = 500;
You can loop through it using for..in loop:
for (var key in myArray) {
console.log("key " + key + " has value " + myArray[key]);
}
See ...
How to parse JSON in Scala using standard Scala classes?
...ult = JSON.parseFull(jsonStr)
result match {
// Matches if jsonStr is valid JSON and represents a Map of Strings to Any
case Some(map: Map[String, Any]) => println(map)
case None => println("Parsing failed")
case other => println("Unknown data structure: " + other)
}
...